how to prettyprint a single-quoted JSON file using jq

{ 'abc': { 'name': 'John', 'address': 'USA' }, 'xyz': { 'name': 'Robert', 'address': 'Canada' } }

1. The sample is not valid JSON.

2. jq can be used to pretty-print valid JSON, though there are some important caveats, mainly about numbers. For example:

   $ jq . <<< '{ "abc": { "name": "John", "address": "USA" }, "xyz": { "name": "Robert", "address": "Canada" } }'  
   {
     "abc": {
       "name": "John",
       "address": "USA"
     },
     "xyz": {
       "name": "Robert",
       "address": "Canada"
     }
   }
   

3. See the jq FAQ for information about converting not-quite-valid JSON to JSON -- search for not-quite-valid.

4. At least one of the tools mentioned in the above-referenced section in the jq FAQ (jsonlint) will not only convert single-quoted quasi-JSON to JSON, but also pretty-print it.

5. In the example you gave, you could use sed or even tr in conjunction with jq:

   echo "{ 'abc': { 'name': 'John', 'address': 'USA' }, 'xyz': { 'name': 'Robert', 'address': 'Canada' } }" |
     tr "'" '"' | jq .
   {
     "abc": {
       "name": "John",
       "address": "USA"
     },
     "xyz": {
       "name": "Robert",
       "address": "Canada"
     }
   }